Craftsmen, e.g. carpenters, plumbers, etc, are frequently in need of a step stool as well as a suitable workpiece support device. For instance carpenters make use of a sawhorse.
U.S. Pat. No. 5,265,697 discloses a sawhorse that is easily assembled and disassembled. The sawhorse has four legs, a top rail and a shelf. The shelf is designed to function as a step, so that a person can stand on the shelf, e.g. to reach an eight foot ceiling. This sawhorse is of limited versatility both with regard to its climbing function as to its workpiece support function.